tracing broken on JRuby with Manticore transport

[kares]

curl style tracing with Elasticsearch::Client.new(trace: true) assumes headers method on the transport client.
however, this isn't the case with Manticore and simply fails, sample reproducer:

require "elasticsearch"
require "elasticsearch/transport/transport/http/manticore"

client = Elasticsearch::Client.new(transport_class: ::Elasticsearch::Transport::Transport::HTTP::Manticore, trace: true)
client.search(q: '*', size: 2)

NoMethodError: undefined method `headers' for #<Manticore::Client:0xf29353f>
Did you mean?  head
  perform_request at /opt/local/rvm/gems/jruby-9.2.16.0@ls/gems/elasticsearch-transport-7.5.0/lib/elasticsearch/transport/transport/base.rb:326
  perform_request at /opt/local/rvm/gems/jruby-9.2.16.0@ls/gems/elasticsearch-transport-7.5.0/lib/elasticsearch/transport/transport/http/manticore.rb:71
  perform_request at /opt/local/rvm/gems/jruby-9.2.16.0@ls/gems/elasticsearch-transport-7.5.0/lib/elasticsearch/transport/client.rb:152
           search at /opt/local/rvm/gems/jruby-9.2.16.0@ls/gems/elasticsearch-api-7.5.0/lib/elasticsearch/api/actions/search.rb:91

[picandocodigo]

Hi @kares, thanks for reporting this! I'm taking a look into this right now. Once I write a fix, I can backport it to 7.13 and 7.14, but 7.5 is not supported anymore. Is this for 7.5?

[kares]

Hey, thanks for looking into this - not really that important just something I've run into while debugging another issue 😉
It's fine to fix in next 7.x minor or whatever is supported e.g. 7.14.1 would be nice to have.